DESCRIPTION: Although a staggering amount of new structural and dynamical information has been obtained regarding the molecular recognitions processes involving the ubiquitous calcium-binding regulatory protein, calmodulin (CaM), much remains to be understood. This is the overarching goal of the continuing studies proposed by Dr. Joshua Wand, whose research efforts over the past decade have contributed significantly to our growing knowledge. In particular, Dr. Wand proposes to use both conventional and novel NMR techniques to study representatives of three different classes of interactions involving CaM: calcium-dependent target binding, calcium-independent target binding, and the binding of target proteins that contain multiple CaM-binding domains. In order to understand fully the intricate interplay of CaM with its many cellular targets, detailed information about all types of interactions will be needed. The studies proposed by Dr. Wand for the next funding period of this 10-year effort should contribute significant new information and insights.